Table 2.

Levels of binding and neutralizing antibodies (either against BA.1 and BA.5) just before the booster administration and after 14, 90, and 180 days. Levels of binding antibodies are expressed in BAU/mL and neutralizing antibodies in a dilution titer⁻¹. NS, *, **, and *** refer to a p-value >0.05 (non-significant), 0.05 to 0.01, 0.01 to 0.001, and 0.001 to <0.0001.

Days	Binding Ab (BAU/mL)			BA.1 NAbs (dilution−1)			BA.5 NAbs (dilution−1)
	mRNA-1273	BNT162b2	P-value	mRNA-1273	BNT162b2	P-value	mRNA-1273	BNT162b2	P-value
0	3234 (2118–4349)	1792 (1170–2414)	0.0244, *	24.6 (17.1–32.2)	18.3 (13.2–23.4)	0.1650, NS	14.3 (11.4–17.2)	14.2 (11.3–17.0)	0.9516, NS
14	20,601 (19,147–22,054)	18,318 (16,292–20,343)	0.0621, NS	473.0 (406.0–540.0)	291.0 (179.0–404.0)	0.0039, **	263.0 (219.0–307.0)	169.0 (100.0–237.0)	0.0166, *
90	14,890 (12,506–17,275)	11,880 (9677–14,082)	0.0648, NS	182.0 (137.0–228.0)	45.2 (32.0–39.3)	<0.0001, ***	86.2 (59.8–113.0)	25.2 (18.9–31.5)	<0.0001, ***
180	10,747 (7190–14,303)	8887 (6268–11,505)	0.3799, NS	62.0 (30.1–93.9)	29.3 (19.3–39.3)	0.0354, *	27.8 (11.7–43.9)	17.8 (13.1–22.4)	0.1696, NS